The field of the present invention is adapters used in well casings for the setting of a sand control liner.
In wells, the control and exclusion of sand and other particulate matter so as not to be entrained into the extracted liquid is of substantial benefit. To this end, a conventional device employed for controlling such matter is a cylindrical liner having small perforations through which oil or other extracted liquid can pass. The perforations are sized to prevent the free passage of sand or other material which may exist in the formation.
To insure sufficient clearance through the irregular interior of a well casing for placement at the bottom of a well, such liners must be smaller in diameter than the casing through which they are to pass. Thus, the placement of a liner at the end of a casing further requires a closure of that clearance between the casing and the liner. To do so, the setting of the liner conventionally includes the use of a sand control adapter which couples with the liner, extends into the end of the adjacent well casing and has a seal capable of expansion outwardly against the inner wall of the casing. The seal is designed to close the clearance between the liner diameter and the inside of the well casing required for practical insertion through the well casing.
To accomplish the foregoing, sand control adapters have been developed which typically are joined to one end of a conventional liner by threads or other common mechanisms. The adapter includes a malleable sleeve concentrically fixed at one end to the outside of the cylindrical wall of the adapter. The sleeve may be expanded outwardly to engage the casing. Some form of deforming mechanism must also be provided at the bottom of the well for the deformation of the sleeve. The energy for deformation may be supplied by a hydraulic mechanism or the hammering of a tool against the sleeve by manipulation of the drill string.
Certain difficulties must be overcome in the employment of this technique. The remote location of the setting requires that the elements be positionable in the well without the risk of a premature expansion of the seal. Uniform expansion of the seal to the casing and accommodation of irregularities in that casing are also important.
Prior devices have been designed which accomplish a setting of a liner including the expansion of a malleable seal against the inner wall of the casing. One such device is illustrated in the Townsend et al. patent, U.S. Pat. No. 4,796,706, issued Jan. 10, 1989, the disclosure of which is incorporated herein by reference. In the Townsend et al. device, a cylindrical liner has an elongated tubular setting sleeve mounted to one end. The elongated tubular setting sleeve includes an annular sealing flange extending outwardly and then concentrically with the sleeve. A tubular flaring sleeve is telescoped together with the elongated tubular setting sleeve with guide slots and guide pins restricting relative axial movement. The flaring sleeve includes a beveled cylindrical end which, when forced or hammered against the sealing flange, causes the sealing flange to deform outwardly against the casing. When initially placed in the well, a nut associated with the drill string is fully threaded into the tubular flaring sleeve such that the sleeve cannot prematurely engage the annular sealing flange. Once positioned, the nut is backed off from that position allowing transmission through the nut of impacting force against the sealing flange.